This invention belongs to the field of agricultural chemistry, and provides to the art a new method of reducing the vigor of unwanted plants. It is well known that the growth of plants out of place has extremely deleterious effects on the crops which are infested with the unwanted plants. Unwanted plants growing in cropland, as well as in fallow land or in land intended to be kept permanently bare, consume soil nutrients and water. Thus, such plants constitute a serious drain on the resources of the soil. When growing in cropland, such plants also shade the crop plants from the sun.
Compounds such as are used in this invention have not previously been known to be useful agricultural chemicals. The closest known related herbicidal compounds are the uretidin-2,4-diones of Belgian Pat. No. 768,051.
The compounds used in this invention were disclosed by Perelman, U.S. Pat. No. 3,194,801, who stated that the compounds have effects on the central nervous system. Related compounds have recently been disclosed to have enzymatic activities, U.S. Pat. No. 3,816,408. Further .beta.-lactam compounds, somewhat related to those of the present invention, were discussed as antibiotics by Bose et al., J. Med. Chem. 17, 541-44 (1974).